In this video,
you will use a repeat loop to fill the blank stage
with different colored objects.
Watch a video demonstration first
then you get to try it on your own.
Your starter project already has a sprite
with several colored objects
that will be used to fill the stage.
Click on sprite to add the code blocks
that will give the sprite instructions.
This sprite will move around stamping copies of itself
onto the stage until the stage is full.
To make that happen click the motion menu
and choose a go to block.
This will move your sprite to a location
on the stage when you click the block.
The sprite needs to move all over the screen
until the stage is full,
and you don't want to waste time to make that happen.
To speed up the process click on the operators menu
and drag the pick random block into the go to x-value.
If you click the block now you will
see that the sprite moves,
just a little every time you click it.
The value in x indicates the position
that the sprite should move
to the left or right on the stage.
The width of the stage stretches from negative 240
to positive 240, so you add those values
to the pick random block.
Now, the computer can pick a random number
anywhere from the far left to the far right on the stage.
You'll also do the same thing for the y-value
so that the sprite can move up and down on the stage.
The height of the stage stretches from negative 180
to positive 180.
When the block is clicked multiple times,
the sprite moves all over the stage.
Next, you need to make it copy itself.
To do that, go to the pen menu,
and add the stamp block to your stack.
It's always a good idea to test your code every step
of the way to make sure it is doing what you like.
Go ahead and click on this stack to make sure the sprite
is moving and stamping.
Of course, you don't want to click the stack yourself
to fill the screen, so under the control menu,
grab the repeat 10 block and put it around your block stack.
If you click the stack now, you see that the block stack
runs 10 times, moving and stamping itself across the screen.
The person using your project should be able
to start it easily, so add the when flag clicked block
to the top of your stack.
This will start the code as soon as someone clicks the flag.
You'll also want the project to start with a blank stage.
To do this, click on the pen menu and use the clear block.
Place the clear block right
under the when flag clicked block so that the screen
is cleared as soon as the project is started.
Each time the flag is clicked, the screen clears
and a new set of colorful objects is stamped.
But, you might want to add more objects
to fill up the space on the screen,
so tinker with the value in the repeat block
until you find one you like.
Changing the repeat number will change the number of times
the blocks and side to repeat loop are run
and the number of times your sprite is stamped.
The best way to catch bugs in your program and fix them
is to test your code often.
If the first solution you try doesn't work, try again.
It's one of the ways computer scientists like you
create projects that they are proud of.
Now it's your turn.
Click on sprite with all of the objects
before adding your code.
Make the sprite move using the go to and pick random blocks.
Then, make the sprite stamp itself
and use a repeat loop to run the code many times.
Use the when flag clicked block and clear block
to start your project.
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